The present disclosure relates to video processors, and more particularly to video processors according to a High Definition Multimedia Interface (HDMI) standard and systems using the video processors.
According to the HDMI standard, in which a high-definition image is transmitted as uncompressed digital data, the data transmitted from a transmitter needs to meet the CEA-861 standard, which is the standard for uncompressed digital video. The CEA-861 standard defines a valid pixel region in horizontal and vertical directions.
Where data having a smaller valid pixel region than the valid pixel region defined by the CEA-861 standard is input to an HDMI transmitter circuit, insufficient pixels relative to the valid pixel region according to the CEA-861 standard are colored black and then the data is output. For example, where 714-pixel data is input to a horizontal valid region of 720 pixels according to the CEA-861 standard, three pixels on each of the right and left in the horizontal direction are colored black, and then the data is output.
However, according to the HDMI standard, when color-difference signals are transmitted from a transmitter in the form of Cb0, Cr0, Cb1, . . . , the receiver recognizes that the signals start from Cb. That is, where the odd number of pixels are colored black on each of the right and left sides in the horizontal direction, as described above, the receiver recognizes the inverted version of the original color-difference signals.
A conventional television signal processor includes a horizontal compression circuit for automatically determining the aspect ratio of 4:3 (normal) or 16:9 (wide) in a wide-screen television and for efficiently utilizing the display as much as possible. However, this television signal processor fails to solve the problem occurring in coloring black, insufficient pixels for a valid pixel region according to the CEA-861 standard to output data.
Therefore, there is a need for a video processor, which outputs video data not causing color inversion at a receiver, even if a pixel region of input video data has a size out of the specification.